Stack Overflow
Q&A for professional and enthusiast programmers
Code Golf
Q&A for programming puzzle enthusiasts and code golfers
Role-playing Games
Q&A for gamemasters and players of tabletop, paper-and-pencil role-playing games
Ask Different
Q&A for power users of Apple hardware and software
Mathematics
Q&A for people studying math at any level and professionals in related fields
Movies & TV
Q&A for movie and TV enthusiasts
Biology
Q&A for biology researchers, academics, and students
Chemistry
Q&A for scientists, academics, teachers, and students in the field of chemistry
English Language Learners
Q&A for speakers of other languages learning English
Software Engineering
Q&A for professionals, academics, and students working within the systems development life cycle
Electrical Engineering
Q&A for electronics and electrical engineering professionals, students, and enthusiasts
Code Review
Q&A for peer programmer code reviews
Meta Stack Exchange
Q&A for meta-discussion of the Stack Exchange family of Q&A websites
Science Fiction & Fantasy
Q&A for science fiction and fantasy enthusiasts
Theoretical Computer Science
Q&A for theoretical computer scientists and researchers in related fields
Arqade
Q&A for passionate videogamers on all platforms
Super User
Q&A for computer enthusiasts and power users
Raspberry Pi
Q&A for users and developers of hardware and software for Raspberry Pi